Detecting a distance between a conducted electrical weapon and a target

ABSTRACT

The number of pulses of a stimulus signal provided by a conducted electrical weapon (“CEW”) between launch and establishing an electrical circuit with a human or animal target may be counted to determine the distance between the CEW and the target and the distance between electrodes launched by the CEW toward the target while positioned in or near target tissue.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of, and claims priority to and thebenefit of, U.S. Nonprovisional patent application Ser. No. 16/003,880,filed Jun. 8, 2018, and entitled “SYSTEMS AND METHODS FOR DETECTING ADISTANCE BETWEEN A CONDUCTED ELECTRICAL WEAPON AND A TARGET,” which is anonprovisional of, and claimed priority to and the benefit of U.S.Provisional Patent Application No. 62/637,079, filed Mar. 1, 2018 andentitled “SYSTEMS AND METHODS FOR A DETECTING A DISTANCE BETWEEN ACONDUCTED ELECTRICAL WEAPON AND A TARGET,” each of which are herebyincorporated by reference in their entirety.

FIELD OF THE INVENTION

Embodiments of the present invention relate to conducted electricalweapons.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

Embodiments of the present invention will be described with reference tothe drawing, wherein like designations denote like elements, and:

FIG. 1 is a block diagram of a portion of a deployment unit and aportion of a handle of a conducted electrical weapon (“CEW”) thatcooperate to detect a distance between the CEW and a target according tovarious aspects of the present disclosure;

FIG. 2 is a diagram of an implementation of the CEW of FIG. 1;

FIG. 3 is a diagram showing wire-tethered electrodes launched from a CEWand a target, the CEW and the target separated by a distance;

FIG. 4 is a diagram of a series of pulses of current of a stimulussignal generated by the CEW;

FIG. 5 is a diagram of a circuit of a CEW for providing a stimulussignal and detecting the distance between the CEW and a target;

FIG. 6 is a diagram of the electrical signals of the circuit of the CEWof FIG. 5 for detecting the distance between the CEW and the target;

FIG. 7 is another diagram of the electrical signals of the circuit ofthe CEW of FIG. 5;

FIG. 8 is another diagram of the electrical signals of the circuit ofthe CEW of FIG. 5;

FIG. 9 is a diagram showing a CEW and a separation of the wire-tetheredelectrodes shortly after launch of the electrodes; and

FIG. 10 is a flow chart of a method for detecting a distance between aCEW and a target according to various aspects of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

A conducted electrical weapon (“CEW”) is a device that provides astimulus signal to a human or animal target to impede locomotion of thetarget. A CEW may include a handle and one or more removable deploymentunits (e.g., cartridges). A removable deployment unit inserts into a bayof the handle. An interface may electrically couple the removabledeployment unit to circuitry in the handle. A deployment unit mayinclude one or more wire-tethered electrodes (e.g., darts) that arelaunched by a propellant toward a target to provide the stimulus signalthrough the target. A stimulus signal impedes the locomotion of thetarget. Locomotion may be inhibited by interfering with voluntary use ofskeletal muscles and/or causing pain in the target. A stimulus signalthat interferes with skeletal muscles may cause the skeletal muscles tolockup (e.g., freeze, tighten, stiffen) so that the target may notvoluntarily move.

A stimulus signal may include a plurality of pulses of current (e.g.,current pulses, pulse). Each pulse of current delivers a current (e.g.,amount of charge) at a voltage. The voltage of a pulse of current mayvary over time. A pulse of a stimulus signal may include an ionizationportion and a muscle portion. The voltage of the ionization portion maydiffer from the voltage of the muscle portion.

A voltage of the ionization portion may be of sufficient magnitude(e.g., 25,000-50,000 volts) to ionize air in a gap between an electrodeand a target. A high voltage in the range of about 50,000 volts canionize air in a gap of up to about one inch. Ionizing air in a gapbetween an electrode and a target establishes an ionization path betweenthe electrode and target tissue. An ionization path has a lowerimpedance than the gap of air. The ionization path establishes anelectrical coupling between the electrode and target tissue. Anelectrode will remain coupled to target tissue during the time that theair in the gap remains ionized. The air in the gap remains ionized aslong as a current is provided to the target via the ionization path.When the current of the stimulus signal provided via the ionization pathceases or is reduced below a threshold, the ionization path collapses(e.g., ceases to exist) and the terminal or electrode is no longerelectrically coupled to target tissue. Electrically coupling anelectrode to a target electrically couples the CEW to the target.

An electrode may also electrically couple to a target via physicalcontact (e.g., embedded into target tissue) of the electrode with targettissue.

Once an electrode is electrically coupled to target tissue, the muscleportion of the stimulus signal may be delivered to the target. Themuscle portion provides current through the target to impede locomotionof the target. The muscle portion of the stimulus signal may bedelivered at a voltage (e.g., 500-5,000 volts) that is lower than theionization portion because the electrode is electrically coupled totarget tissue either by an ionization path or contact. The muscleportion of the stimulus circuit delivers electric charge through thetarget to impede locomotion of the target.

A stimulus signal is generated by a signal generator. The signalgenerator may be controlled by a processing circuit. The processingcircuit may also control a launch generator. The processing circuit mayreceive input from a user interface, and possibly information from othersources. The user interface may be as simple as a safety switch (e.g.,on/off) and a trigger that is pulled to operate the CEW. An example ofinformation from other sources may be a signal that indicates that adeployment unit is loaded into a bay in the handle and is ready for use.

A processing circuit may send commands to the launch generator to launchone or more wire-tethered electrodes and/or engage the signal generatorbased on input received from the user interface or other possiblesources. Upon receiving a launch command from the processing circuit,the launch generator activates the propulsion system to provide a forceto launch one or more electrodes.

The electrodes may be positioned in a deployment unit. The position ofan electrode in a deployment unit may establish the trajectory of launchof the electrode. In a deployment unit with one or more electrodes, thetrajectory of launch for each electrode may be different. For example,the electrodes are positioned so that there is an angle of launchbetween the electrodes. The angle between the trajectories is set toincrease the separation of the electrodes from each other in accordancewith the distance that the electrodes travel away from the CEW. Thefurther the electrodes travel to the target the greater the separationof the electrodes on the target.

Increased separation of the electrodes on the target improves theeffectiveness of the stimulus signal in stopping voluntary movement ofthe target. Separation may improve the effectiveness of the stimulussignal by increasing the amount of target tissue affected by thestimulus signal. A separation of the electrodes at the target of atleast 6 inches is preferred.

Because the electrodes separate from each other in-flight, the distancebetween the CEW and the target provides information as to the separationof the electrodes when they reach a target. The separation between theelectrodes at the target, provides information as to the possibleeffectiveness of the stimulus signal in stopping locomotion of thetarget. Accordingly, it is beneficial to know distance between the CEWand the target. The distance between the CEW and the target may berecorded (e.g., stored). Recording the distance between the CEW and thetarget may be useful in establishing the facts of an event. Havingunbiased facts of the event may be useful in resolving conflictingtestimony.

For example, CEW 100 in FIG. 1, includes deployment unit 110 and handle130. Deployment unit 110 includes electrode 112, electrode 114, andpropulsion system 116. Handle 130 includes signal generator 132, launchgenerator 134, processing circuit 136, user interface 138, memory 140,communication circuit 142, and launch signal 150.

A deployment unit cooperates with a handle to launch one or morewire-tethered electrodes toward a target to provide a stimulus signal tothe target. A deployment unit may include a propulsion system. Apropulsion system provides a force (e.g., a rapidly expanding gas) tolaunch the one or more wire-tethered electrodes. A deployment unit mayreceive a signal from a handle to launch the electrodes of thedeployment unit. A propulsion system may be activated by a launch signalfrom the handle to launch the one or more electrodes from the deploymentunit. Each electrode may be electrically coupled to a deployment unitvia a wire tether (e.g., filament). A handle may provide a stimulussignal to a deployment unit, which in turn provides the stimulus signalto the one or more electrodes via the respective filaments of theelectrodes. The stimulus signal may ionize air in a gap between theelectrodes and/or between an electrode and a target to electricallycouple the electrodes to target tissue as discussed above. The stimulussignal may include a muscle portion to impede locomotion as discussedabove.

An electrode, as discussed above, couples to a wire tether and islaunched toward a target to deliver a stimulus signal through thetarget. Movement of an electrode out of a deployment unit toward atarget deploys (e.g., pulls) the wire tether so that it extends from thedeployment unit (e.g., cartridge) in the handle to the electrode at thetarget. Launching an electrode deploys the wire tether, so that itbridges (e.g., covers, extends across) the distance between the CEW andthe target. An electrode may be formed of a conductive material (e.g.metal, semiconductor) for delivery of the stimulus signal into targettissue. An electrode may include structures (e.g., spear, bars) formechanically coupling the electrode to the target.

A signal generator generates a stimulus signal for delivery through ahuman or animal target to impede locomotion of the target. A signalgenerator may provide a stimulus signal to a target via wire-tetheredelectrodes. A signal generator may provide a stimulus signal between twoelectrodes positioned in or proximate to target tissue so that thestimulus signal conducts through target tissue. Increasing theseparation of the electrodes in or on a target, increases the area oftarget tissue affected by the stimulus signal. Increasing the area oftarget tissue affected by the stimulus signal increases the likelihoodthat the stimulus signal may interfere with skeletal muscles of thetarget to cause the skeletal muscles to lock-up. Locking up the skeletalmuscles of a target interferes with target locomotion. Providing thestimulus signal through target tissue to cause pain in the targetinterferes with target locomotion.

A stimulus signal may include a series of current pulses as discussedabove. The pulses of a stimulus signal may be provided at a pulse rate.Each pulse of a stimulus signal provides an amount of electrical chargeto the target. The signal generator may provide the stimulus signal at apulse rate and amount of charge per pulse to increase a likelihood ofimpeding locomotion of a target. Increasing the pulse rate and/or amountof charge delivered per pulse increases the likelihood of impedinglocomotion of the target by locking up the muscles of the target. Asignal generator may provide a stimulus signal at a first pulse ratethen a second pulse rate. One pulse rate may be better suited fordetecting a distance between the CEW and a target, while another pulserate may be better suited for impeding locomotion.

Each pulse of a stimulus signal may be provided at a voltage. A signalgenerator may provide a stimulus signal at a voltage of sufficientmagnitude to ionize air in one or more gaps in series with the signalgenerator and the target as discussed above. Ionization of air in one ormore gaps may electrically couple the signal generator to the target viathe wire-tethered electrodes.

A pulse of a stimulus signal may include a high voltage portion (e.g.,ionization portion) for ionizing air in gaps to establish electricalcoupling and lower voltage portion (e.g., muscle portion) for providingcurrent through target tissue to impede locomotion of the target asdiscussed above.

A signal generator includes circuits for receiving electrical energyfrom a source (e.g., battery) and for providing (e.g., generating) thestimulus signal. Electrical/electronic components in the circuits of asignal generator may include capacitors, resistors, inductors, sparkgaps, transformers, silicon-controlled rectifiers (SCRs), andanalog-to-digital converters. A processing circuit may cooperate withand/or control the circuits of a signal generator to produce a stimulussignal.

For example, activation of propulsion system 116 launches electrodes 112and 114 toward a target. Propulsion system 116 provides an expanding gasto launch (e.g., push, propel) electrodes 112 and 114 toward a target.As electrodes 112 and 114 fly toward the target, a respective conductivefilament (not shown) extends between deployment unit 110 and electrodes112 and 114. The filaments electrically couple electrode 112 andelectrode 114 to signal generator 132. Signal generator 132 provides thestimulus signal to the target via the filaments and electrodes 112 and114. While electrode 112 and/or electrode 114 are proximate to, but notembedded in, target tissue, the stimulus signal ionizes air in gapsbetween electrode 112 and the target and/or electrode 114 and the targetto form a circuit to deliver the stimulus signal through the target. Thecircuit includes a first wire tether (not shown) electrically andmechanically coupled to electrode 112, electrode 112, target tissue,electrode 114, and a second wire tether (not shown) electrically andmechanically coupled to electrode 114. Signal generator 132 electricallycouples to deployment unit 110 and the first wire tether and the secondwire tether to provide the stimulus signal through the circuit.

As discussed above, a propulsion system provides a force (e.g. a rapidlyexpanding gas) to launch electrodes toward a target. Electrodes land(e.g., impact, strike) in or near target tissue to deliver a stimulussignal through a target to impede locomotion of the target. A propulsionsystem may include a canister that is filled with a compressed gas.Piercing (e.g., puncturing, opening) the canister releases the gas. Therapid expansion of the gas from the canister provides a force forlaunching electrodes.

A handle performs the functions of a CEW and cooperates with adeployment unit to deliver a stimulus signal to a target. A handle mayinclude a processing circuit. A processing circuit may control theoperation of the components and/or circuits of a handle to perform thefunctions of the handle discussed herein. A handle may include a userinterface for enabling activation (e.g., triggering) and control by auser. A handle may include a signal generator. A signal generatorprovides the pulses of current of a stimulus signal. A handle mayinclude a source of energy for providing the stimulus signal andperforming the functions of a CEW. A source of energy may include abattery. A handle may accept (e.g., receive) one or more deploymentunits. A handle may include one or more bays for receiving a respectivedeployment unit. A deployment unit may be removeable inserted into a bayof a handle for deploying one or more wire-tethered electrodes toprovide the stimulus signal to a target. A handle may include a launchgenerator. A launch generator provides a signal for launching theelectrodes of a deployment unit.

A launch generator includes a circuit that provides a launch signal. Aprocessing circuit may control the operations of a launch generator inwhole or in part. A processing circuit may instruct a launch circuit toprovide a launch signal responsive to an input (e.g., trigger pull)provided by the operator of the CEW. Responsive to receiving a signal(e.g., command) from a processing circuit, a launch generator mayprovide a signal to one or more deployment units to initiate a launch ofone or more electrodes from the deployment unit. The signal provided bya launch generator to a deployment unit to initiate launch of electrodesmay be referred to as a launch signal.

A processing circuit includes any circuitry and/or electrical/electronicsubsystem (e.g., component, devices) for performing a function. Aprocessing circuit may include circuitry that performs (e.g., executes)a stored program. A processing circuit may include a digital signalprocessor, a microcontroller, a microprocessor, an application specificintegrated circuit, a programmable logic device, logic circuitry, statemachines, MEMS devices, signal conditioning circuitry, communicationcircuitry, a computer (e.g., server), a radio, a network appliance, databusses, address busses, and/or a combination thereof in any quantitysuitable for performing a function and/or executing one or more storedprograms.

A processing circuit may further include conventional passive electronicdevices (e.g., resistors, capacitors, inductors) and/or activeelectronic devices (op amps, comparators, analog-to-digital converters,digital-to-analog converters, current sources, programmable logic). Aprocessing circuit may include data buses, output ports, input ports,timers, memory, and arithmetic units.

A processing circuit may provide and/or receive electrical signalswhether digital and/or analog in form. A processing circuit may provideand/or receive signals (e.g., data, information) via a bus using anyprotocol. A processing circuit may receive information, manipulate thereceived information, and provide the manipulated information. Aprocessing circuit may store information and retrieve storedinformation. Information received, stored, and/or manipulated by theprocessing circuit may be used to perform a function and/or to perform astored program.

A processing circuit may control the operation and/or function of othercircuits and/or components of a system. A processing circuit may receivestatus information regarding the operation of other components (e.g.,status, feedback). A processing circuit may perform calculations (e.g.,operations) with respect to the status information. A processing circuitmay provide commands (e.g., signals) to one or more other components inaccordance with calculations. For example, a processing circuit mayrequest the status of a component, analyze the status, and commandcomponents to start operation, continue operation, alter operation,suspend operation, or cease operation responsive to the status. Commandsand/or status may be communicated between a processing circuit and othercircuits and/or components via any type of bus including any type ofdata/address bus.

A handle may include a processing circuit. A processing circuit maycontrol the operation of the components and/or circuits of a handle toperform the functions of the handle discussed herein. A processingcircuit may detect input from a user interface (e.g. trigger). Aprocessing circuit may control launch of electrodes (e.g., via a launchgenerator). A processing circuit may control activation of the stimulussignal (e.g., via a signal generator). A processing circuit incooperation with other components may detect the magnitude of thevoltage of a pulse of a stimulus signal. A processing circuit incooperation with other components may detect the magnitude of thevoltage of (e.g., across, on) a capacitance. A processing circuit maydeduce information from the magnitude of the voltage. A processingcircuit may select a pair of electrodes to deliver a stimulus signal tothe target.

A processing circuit may store information in a memory regarding theoperation of the handle, the operation of a deployment unit, duration oftime or an event, voltage magnitudes, and/or information deducedregarding the voltage magnitudes. A processing circuit may report storedinformation to a server and/or a user. A processing circuit may provideinformation to a user via a user interface.

A memory may store information. A memory may provide previously storedinformation. A memory may provide previously stored informationresponsive to a request for information. A memory may store informationin any format. A memory may store electronic digital information. Amemory may provide stored data as digital information. Stored data mayinclude a stored program for execution by a processing circuit. A memorymay store information regarding the operation of the handle, theoperation of a deployment unit, duration of time of an event, voltagemagnitudes measured with respect to pulses of the stimulus signal, andinformation deduced regarding the voltage magnitudes and or duration oftime of an event.

A memory includes any semiconductor, magnetic, optical technology, orcombination thereof for storing information. A memory may receiveinformation from a processing circuit for storage. A processing circuitmay provide a memory a request for previously stored information.Responsive to the request, the memory may provide stored information toa processing circuit.

A memory may include any circuitry for storing program instructions(e.g., stored program) and/or data. Stored data may be organized in anymanner (e.g., program code, buffer, circular buffer). Memory may beincorporated into and/or accessible by a launch generator, a signalgenerator, a user interface, a communication circuit, and/or aprocessing circuit.

A user interface enables a human user to interact with an electronicdevice (e.g., handle). A user may control, at least in part, anelectronic device via the user interface. A user may provide informationand/or commands to an electronic device via a user interface. A user mayreceive information (e.g., status) and/or responses from the electronicdevice via the user interface.

A user interface may include one or more controls that permit a user tointeract and/or communicate with (e.g., provide information to) anelectronic device to control (e.g., influence) the operation (e.g.,functions) of the electronic device. A control includes anyelectromechanical device suitable for manual manipulation by a user. Acontrol includes any electromechanical device for operation by a user toestablish or break an electrical circuit. A control may include aportion of a touch screen. Operation of a control may occur by theselection of a portion of a touch screen. A control may include aswitch. A switch includes a pushbutton switch, a rocker switch, a keyswitch, a detect switch, a rotary switch, a slide switch, a snap actionswitch, a tactile switch, a thumbwheel switch, a push wheel switch, atoggle switch, a reed switch, and a key lock switch (e.g., switch lock).

A control may be operated in different manners by a user to providedifferent information to a processing circuit. For example, in animplementation in which the control is implemented as a push button, auser may press and release the button; press, hold the button for aperiod of time, then release the button during which the period of timefor which the button is held determines the information conveyed to aprocessing circuit. The duration of time a control may be held mayinclude a short press, a long press, and a very long press. A controlmay be pressed and released multiple times to convey information (e.g.,double press).

The term “control”, in the singular, represents a singleelectromechanical device for operation by a user to provide informationto a device. The term “controls”, in plural, represents a plurality ofelectromechanically devices for operation by a user to provideinformation to a device. The term “controls” include at least a firstcontrol and a second control. Trigger 238 may be implemented as acontrol.

As discussed above, a user interface may provide information to a user.A user may receive visual, haptic (e.g., tactile, kinesthetic), and/oraudible information from a user interface. A user may receive visualinformation via devices (e.g., indicators) that visually displayinformation (e.g., LCDs, LEDs, light sources, graphical and/or textualdisplay, display, monitor, touchscreen). A user may receive audibleinformation via devices that provide an audible sound (e.g., speaker,buzzer). A user may receive tactile information via devices thatvibrate, move, and/or change resistance against a user's finger as it ispressed.

A communication circuit transmits and/or receives information (e.g.,data). A communication circuit may transmit and/or receive (e.g.,communicate) information via a wireless and/or wireless communicationlink. A communication circuit may communicate using wireless (e.g.,radio, light, sound, vibrations) and/or wired (e.g., electrical,optical) mediums. A communication circuit may communicate using anywireless (e.g., Bluetooth, Zigbee, WAP, WiFi, NFC, IrDA, LTE, BLE, EDGE,EV-DO) and/or wired (e.g., USB, RS-232, Firewire, Ethernet)communication protocols.

A communication circuit may receive information from a processingcircuit for transmission. A communication circuit may provide receivedinformation to a processing circuit.

A communication circuit in one device (e.g., handle, CEW) maycommunicate with a communication circuit in another device (e.g., smartphone, laptop, tablet). Communications between two devices may permitthe two devices to cooperate in performing a function of either device.For example, all or a portion of a user interface for a CEW may beimplemented on a smart phone that includes a touch screen. Userinteraction with the user interface on the smart phone is communicatedto the CEW via the communication circuits of the smart phone and CEW.The CEW performs the function indicated by the message from the smartphone. Any information produced by the CEW for the user is communicatedfrom the CEW to the smart phone via the communication circuits fordisplay on the display of the smart phone.

A communication circuit may transmit information to and/or receiveinformation from a server. A communication circuit may transmitinformation stored in a memory of a CEW to a server for storage and/oranalysis.

CEW 200 of FIG. 2 is an implementation of CEW 100. CEW 200 in FIG. 2,includes deployment unit 210, deployment unit 220, and handle 230.Handle 230 includes trigger 238. Deployment unit 210 and 220 perform thefunctions of a deployment unit as discussed herein. Handle 230 performsthe functions of a handle as discussed herein. Trigger 238 is part of auser interface of handle 230. Trigger 238 enables a user to initiate alaunch of electrodes and provision of a stimulus signal. Trigger 238enables a user to control, at least in part, the operations of CEW 200.

CEW 200 may include all of the components (e.g., electrodes, propulsiongenerator, launch generator, wire tether, signal generator, processingcircuit, memory, communication circuit) of CEW 100 not specificallyidentified in CEW 200. CEW 200 may perform all of the functions of a CEWdiscussed herein.

A CEW may launch one or more wire-tethered electrodes toward a target toprovide a stimulus signal to the target. The wire-tethered electrodesfly a distanced from the CEW to the target to deliver the stimulussignal to the target. Prior to launch, the electrodes are positioned ina deployment unit in close (e.g., millimeters, fractions of an inch)proximity to each other. As the electrodes fly away from the CEW towarda target, the distance between the electrodes increases because theelectrodes separate from each other as they fly toward the target.

The distance between the electrodes when they reach a target is afunction of the distance the electrodes travel away from the CEW. Thedistance between the electrodes when they strike the target determinesthe amount of target tissue through which the stimulus signal travels.Providing the stimulus signal through more target tissue increases thelikelihood that the skeletal muscles of the target will lock-up therebydenying the target voluntary use of skeletal muscles and therebyinterfering with locomotion of the target. A separation of more than sixinches between the electrodes when they reach (e.g., strike) the targetis preferable for increasing a likelihood of locking-up the skeletalmuscles of the target. Detecting the distance the electrodes have flownfrom the CEW to the target provides information as to the separation ofthe electrodes at the target.

For example, CEW 200 in FIG. 3 has launched wire-tethered electrodes 310and 320 toward target 350. Electrodes 310 and 320 are oriented at angle340 relative to each other while positioned in CEW 200 prior to launch.The relative trajectories of electrodes 310 and 320 are determined byangle 340. Angle 340 causes electrodes 310 and 320 to separate from eachother during flight so that electrodes 310 and 320 are separated fromeach other distance 342 upon reaching target 350. Electrodes 310 and 320have traveled (e.g., flown) distance 330 from CEW 200 to target 350.Wire tethers 312 and 322 extend from CEW 200 to the electrodespositioned in or near the tissue of target 350.

Because the speed (e.g., velocity) of flight of electrodes 310 and 320is known, distance 330 between CEW 200 and target 350 may be determinedby measuring the time of flight of the electrodes between the CEW andthe target. Equation 1, below, may be used to determine distance 330.

d=v*t  Equation no. 1:

The distance between the CEW and the target is d (e.g., 330), thevelocity of the electrodes is v, and the time of flight of theelectrodes is t. A processing circuit may calculate distance 330 becausevelocity of flight of electrode 310 and electrode 320 is a known value.A processing circuit may determine the time of flight, t, because theprocessing circuit may determine (e.g., detect) the time of launch ofelectrodes 310 and 320 and the time when electrodes 310 and 320 haveflown to target 350 and are positioned in or near target tissue.

Having determined distance 330, a processing circuit may furtherdetermine distance 342 between electrode 310 and electrode 320 at target350 because angle 340 is also a known value.

s=d*tan(a)  Equation no. 2:

Where distance 342 between electrode 310 and electrode 320 is s,distance 330 between the CEW 200 and the target 350 is d (see equationno. 1), and angle 340 between electrode 310 and electrode 320 is a. Theprocessing circuit may calculate separation s (e.g., 342) because angle340 is a known value for a deployment unit and distance 330 may bedetermined in accordance with equation no. 1 above.

As discussed above, the pulses of a stimulus signal may be provided atdifferent rates. For example, the pulses of a stimulus signal may beprovided at a first rate followed by a second rate. A stimulus signalwith a higher (e.g., faster) pulse rate may improve the accuracy ofmeasuring the time of flight of the electrodes 310 and 320 from CEW 200to target 350. Providing a stimulus signal at a higher pulse rate, atleast for a predetermined period of time after launch, improves theaccuracy of calculating distance 330 between CEW 200 and target 350.

Pulses of a stimulus signal that are provided at a higher pulse rate maybe provided at a lower voltage than pulses provided at a lower pulserate. Providing pulses at a lower voltage may facilitate providing thepulses at a higher pulse rate (e.g., greater frequency).

A stimulus signal that has pulses provided at a lower voltage, eventhough provided at a higher pulse rate, may not provide the same amountof charge as a stimulus signal that has pulses provided at a highervoltage and a lower pulse rate. A stimulus signal provided at a highervoltage, even though provided at a lower pulse rate, may increase thelikelihood that the stimulus signal interferes with locomotion of atarget by locking up the muscles of the target. So, a stimulus signalwith a first pulse rate that is faster and a second pulse rate that isslower may improve the measurement accuracy of the time of flight of theelectrodes during the period of the faster pulse and impede locomotionof a target during the period of the slower pulse rate.

For example, stimulus signal 450 of FIG. 4 includes pulses during timeT430 that are delivered at a first rate and a lower voltage followed bypulses during time T440 that are delivered at a second rate and a highervoltage. The pulses of time T430 have period T410. The pulses of timeT440 have period T420. Time T410 is less than time T420.

A processing circuit may begin measuring the time of flight ofelectrodes 310 and 320 from CEW 200 toward target 350 beginning at thetime when the launch signal is sent to the deployment unit to launchelectrodes 310 and 320. When the processing circuit detects thatelectrodes 310 and 320 have electrically coupled to target 350 and areproviding the stimulus signal through target 350, the processing circuitmay stop measuring time the time of flight because the flight of theelectrodes has ended and they are positioned at target 350. The durationof time between launch of electrodes 310 and 320 and detecting anelectrical coupling represents the time of flight.

One method for a processing circuit to measure the time of flight is tocount the number of pulses of the stimulus signal between providing thelaunch signal and detecting a circuit with the target. Because thepulses of the stimulus signal are provided at regular intervals, eachpulse represents a distance flown (e.g., covered, traveled) by theelectrodes. A faster pulse rate means that there is less time betweenpulses and therefore less distance traveled for each pulse counted. Asthe pulse rate increases, the accuracy of number of pulses counted tothe distance from CEW 200 to target 350 increases.

For example, Table 1 below provides two different pulse rates of astimulus signal and the corresponding of distance travelled by anelectrode for a pulse of the stimulus signal.

Pulse rate Velocity of Dart Resolution (pulses per second) (feet persecond) (feet per pulse) 22 120 5.5 200 120 0.6

As can be seen from Table 1, a faster pulse rate increases theresolution of measuring distance between the CEW and the target becauseas the pulse rate increases, the electrode travels less distance betweeneach pulse. At 22 pulses per second, the accuracy of counting pulses todetermine distance of flight is accurate to about +/−5.5 feet. Whereasat 200 pulses per second, the accuracy of counting pulses to determinedistance of flight is +/−0.6 feet.

For example, if target 350 is positioned 8 feet away from CEW 200,processing circuit 136 will count one pulse at 22 pulses per secondbefore electrodes 310 and 320 reach target 350. The distance of flightmay be determined to be somewhere between 5.5 feet and 11 feet. However,if the pulses of the stimulus signal are provided at 200 pulses persecond, the processing circuit will count 13 pulses before electrodes310 and 320 reach target 350, so the distance of flight, distance 330,can be determined to be somewhere between 7.8 feet and 8.4 feet.

Circuit 500 of FIG. 5 is an implementation of a circuit that provides astimulus signal at different rates and counts the number of pulsesbetween launch and providing the stimulus signal through a target.

Circuit 500 includes signal generator 132, electrode 310, electrode 320,and processing circuit 136. Signal generator 132 includes switched powersupply 510, capacitance 520, capacitance 522, capacitance 530,transformer 540, control signal 550, control signal 552, and switch 560.Transformer 540 includes primary winding 542, secondary winding 544, andsecondary winding 546.

Capacitance 520 may be referred to as the positive muscle capacitance.Capacitance 522 may be referred to as the negative muscle capacitance.Capacitance 530 may be referred to as the ionization capacitance. Amuscle capacitance may cooperate with other circuits to provide themuscle portion of a stimulus signal. An ionization capacitance maycooperate with other circuits to provide the ionization portion of astimulus signal.

Transformer 540 may be referred to as a high voltage transformer. Thesecondary winding of transformer 540 may provide a voltage in the rangeof 25,000-50,000 volts. Switch 560 may be referred to as an ionizationdischarge switch.

A capacitance may include any active and/or passive component thatstores a charge and provides a charge. A capacitance includes acapacitor.

A control signal may include one or more signals. A control signal maybe provided over a bus that includes one or more conductors.

Processing circuit 136 controls signal generator 132 and switched powersupply 510 to provide a stimulus signal. Processing circuit 136 controlssignal generator 132 and switched power supply 510 to provide each pulseof a stimulus signal. To provide a pulse of a stimulus signal,processing circuit 136 controls switched power supply 510 to chargecapacitances 520, 522, and 530. Once capacitances 520, 522, and 530 arecharged, processing circuit 136 closes switch 560 to dischargecapacitance 530 into primary winding 542 of transformer 540. Responsiveto the discharge of capacitance 530 into primary winding 542,transformer 540 steps up the voltage applied to the primary to produce ahigher voltage across secondary windings 544 and 546 and thereby across(e.g., between) electrodes 310 and 320.

If a circuit is established, by electrodes 310 and 320 through a target,capacitances 520 and 522 discharge into the target via secondary winding544 and secondary winding 546, and electrode 310 and electrode 320respectively. Capacitances 520 and 522 discharged when a circuit isestablished by electrodes 310 and 320 through a target, so the dischargeof capacitances 520 and 522 is a sign that electrodes 310 and 320 haveelectrically coupled to a target. The voltage across capacitances 520and 522 may be monitored to detect when electrodes 310 and 320 dischargeand thereby detect when electrodes 310 and 320 have reached a target.

Each pulse generated by signal generator 132 begins by dischargingcapacitance 530 into primary winding 542. Processing circuit 136controls the charging of capacitance 530 by controlling switched powersupply 510. Processing circuit 136 controls the discharge of capacitance530 by controlling switch 560. Processing circuit 136 also controlssending a launch signal to a deployment unit to launch electrodes fromthe deployment unit toward a target. Processing circuit 136 may alsomonitor the voltage across capacitances 520 and 522.

As a result of the controlling and the monitoring discussed above,processing circuit 136 knows when the electrodes have been launched, maycount the number of pulses of the stimulus signal provided after launch,may detect when and if electrodes 310 and 320 establish a circuitthrough a target, and determine the number of pulses of the stimulussignal provided between launch and reaching the target. Processingcircuit 136 may also be programmed with the information to calculate thedistance between the CEW and a target in accordance with the number ofpulses provided between launch and reaching a target as discussed above.Further, processing circuit 136 may calculate distance 342 betweenelectrode 310 and electrode 320 at the target in accordance with thedistance electrodes 310, or electrode 320, traveled to reach the target.

Referring to FIGS. 6-8, processing circuit 136 in cooperation withswitched power supply 510 and signal generator 132, may produce pulsesof the stimulus signal at a higher rate and lower voltage to aid indetermining the distance between the CEW and a target, followed bypulses of the stimulus signal at a lower rate and higher voltage to aidin impeding locomotion of the target. Processing circuit 136 may countpulses of current at the higher rate to determine distance and detectthe discharge of capacitances 520 and 522 to detect a circuit through atarget via electrodes 310 and 320 as discussed above.

The waveforms of FIGS. 6-8 show the operation of circuit 500 under threedifferent conditions. In FIG. 6, circuit 500 charges and dischargescapacitance 530 at higher pulse rate and lower voltage until circuit 500detect the discharge of capacitance 520, or capacitance 522, whichoccurs when electrodes 310 and 320 have electrically coupled with atarget. After circuit 500 detects that electrodes 310 and 320 haveelectrically coupled to the target, circuit 500 provides pulses of thestimulus signal at a lower pulse rate and higher voltage.

In FIG. 7, electrodes 310 and 320 do not electrically couple with target350, so capacitances 520 and 522 do not discharge. Because capacitances520 and 522 do not discharge, circuit 500 does not detect thatelectrodes 310 and 320 have electrically coupled to a target, so circuit500 charges and discharges capacitance 530 at a higher pulse rate andlower voltage for a predetermined amount of time before providing pulsesof the stimulus signal at a lower pulse rate and higher voltage. In FIG.7, once the stimulus signal is provided at the higher voltage, thehigher voltage ionizes air in a gap between electrodes 310 and 320 andthe target to electrically couple to circuit 500 to target 350.

The waveforms of FIG. 8 show the operation of circuit 500 whenelectrodes 310 and 320 completely fail to electrically couple to atarget. In FIG. 8, circuit 500 does not detect that electrodes 310 and320 have electrically coupled to a target, so circuit 500 charges anddischarges capacitance 530 at higher pulse rate and lower voltage for apredetermined amount of time before providing pulses of the stimulussignal at a lower pulse rate and higher voltage. However, unlike in FIG.7, in FIG. 8 once the stimulus signal is provided at the higher voltagethe higher voltage does not result in an electrical coupling ofelectrodes 310 and 320 to the target.

The waveforms of FIGS. 6-8 are discussed in more detail below.

Referring to FIG. 6, processing circuit 136 may produce pulses of thestimulus signal at a higher rate until processing circuit 136 detectsthat electrodes 310 and 320 have electrical coupled to (e.g.,established a circuit with) a target.

Signal 610 is the voltage at node VMP in FIG. 5, which is the voltageacross capacitance 520. The voltage across node VMN, not shown, issimilar, but of an opposite polarity. Signal 620 is the voltage at nodeVI in FIG. 5, which is the voltage across capacitance 530. Signal 150 isthe launch signal. Prior to launching electrodes 310 and 320, processingcircuit 136 charges capacitance 520 to voltage V614 and capacitance 530to voltage V624. Processing circuit 136 provides launch signal 150(e.g., a pulse) to launch electrodes 310 and 320 toward target 350.Because processing circuit 136 provides launch signal 150, processingcircuit 136 knows that the process for launching electrodes 310 and 320has begun, so processing circuit 136 may begin counting the number oftimes pulses are formed in (e.g., provided by) signal 620.

Processing circuit 136 controls providing pulses of signal 620 at thehigher pulse rate by repeatedly charging capacitance 530 and dischargingcapacitance 530 into primary winding 542 of transformer 540. Each timecapacitance 530 is charged and discharged, a pulse of signal 620 isprovided. Processing circuit 136 controls the discharge of capacitance530 because processing circuit 136 controls switch 560.

Charging capacitance 530 to a voltage of magnitude V624 requires lesstime than charging capacitance 530 to a voltage of magnitude V622 sinceV624 is a lower magnitude than V622. Likewise, charging capacitance 520to a voltage of magnitude V614 requires less time than chargingcapacitance 520 to a voltage of magnitude V612 since V614 is a lowermagnitude than V612.

From the time of launch, at the start of time T630, processing circuit136 controls the charging and discharge of capacitance 530 to formpulses of signal 620 at a first rate. Processing circuit 136 counts thenumber of times capacitance 530 is charged and discharge. Whenelectrodes 310 and 320 establish an electrical circuit with the target,the voltage across capacitance 520, and the voltage (not shown) acrosscapacitance 522, decreases as capacitance 520 and capacitance 522discharge through the target. Processing circuit 136 detects thedischarge of capacitance 520 and capacitance 522. The discharge ofcapacitance 520 and capacitance 522 indicates the end of the time offlight of electrodes 310 and 320. The discharge of capacitance 520 andcapacitance 522 indicates that a circuit has been established with thetarget. Processing circuit 136 may determine the time of flight ofelectrodes 310 and 320 to the target by the number of pulses of signal620 during period T630 (e.g., time from launch to discharge ofcapacitance 520).

Once processing circuit 136 detects discharge of capacitance 520,processing circuit 136 may decrease the pulse rate of signal 620 andincrease the magnitude of the voltages V612 and V622 across capacitance520 (and capacitance 522) and 530 respectively to provide signals 610and 620 at a second rate. Signals 610 and 620 are provided through thecircuit into target tissue as a stimulus signals as discussed above.Signal 620 provides the high voltage portion of the stimulus signal forionizing air in gaps to establish electrical coupling between theelectrodes and the target. Signal 610 provides the lower voltage portionof the stimulus signal through target tissue to impede locomotion of thetarget. The stimulus signal is the combination of signal 610 and signal620.

Discussed only briefly above, the operation of capacitance 522 isanalogous to the operation of capacitance 520 and signal 610 except thatthe polarity of the voltage across capacitance 522 is the opposite ofthe polarity of the voltage across capacitance 520 so that the voltageprovided by capacitances 520 and 522 to target tissue is double theabsolute value of the magnitude of the voltage of signal 610.

In the event that electrodes 310 and 320 do not electrically couple to atarget, capacitance 520, and 522, will not discharge, so processingcircuit 136 does not detect a circuit with a target. As shown in FIG. 6,above, when processing circuit 136 detects that electrodes 310 and 320have coupled to a target, processing circuit 136 shifts from providingpulses at a higher rate to a lower rate. After the predetermined periodof time if no connection with a target is detected, processing circuit136 may produce pulses of the stimulus signal at a lower rate and ahigher magnitude of voltage. Even though the pulse of the stimulussignal provided at the lower voltage could not establish a circuit withthe target, once the predetermined period time elapses and the pulses ofthe stimulus signal are provided at the higher voltage, the highervoltage may establish a circuit through the target by ionizing air in agap between the electrodes and the target.

With respect to the signals shown in FIG. 7, processing circuit 136provides pulses of the stimulus signal at a higher rate and lowervoltage for a predetermined period of time. After the predetermineperiod of time, because processing circuit has not detected thedischarge of capacitance 520, processing circuit 136 provides pulses ata lower rate and higher voltage. As discussed above, the pulses of thestimulus signal provided at the lower rate and higher voltage may ionizeair in a gap between electrodes 310 and 320 and the target to establisha circuit between electrodes 310 and 320 and target tissue.

Signal 710 is the voltage at node VMP in FIG. 5, which is the voltageacross capacitance 520. Signal 720 is the voltage at node VI in FIG. 5,which is the voltage across capacitance 530. Signal 150 is the launchsignal. Prior to launching electrodes 310 and 320, processing circuit136 charges capacitance 520 to voltage V614 and capacitance 530 tovoltage V624. Processing circuit 136 provides launch signal 150 tolaunch electrodes 310 and 320 toward target 350. Processing circuit 136begins to count the number of times pulses are formed in signal 720.

Processing circuit 136 controls providing pulses of signal 720 at thehigher pulse rate by repeatedly charging capacitance 530 and dischargingcapacitance 530 into primary winding 542 of transformer 540. Each timecapacitance 530 is charged and discharged, a pulse of signal 720 isprovided. Processing circuit 136 controls the discharge of capacitance530. Processing circuit 136 discharges capacitance 530 by closing switch560.

Because processing circuit 136 does not detect a decrease in the voltageacross capacitance 520 (e.g., discharge of capacitance 520), processingcircuit provides pules of the stimulus voltage at the higher pulse rateand lower voltage for the predetermined period of time T730. It may bepossible that electrodes 310 and 320 are proximate to target tissue, butseparated from target tissue by a gap of air that too long for the lowermagnitude of the voltage to ionize the air in the gap to establish acircuit with the target.

After the period of time T730, processing circuit 136 provides pulses ofsignal 720 at a lower pulse rate and a higher voltage. Once the pulsesof signal 720 are provided at the higher voltage, the magnitude of thevoltage may be high enough to ionize air in a gap between electrodes 310and 320 to establish a circuit with the target.

As discussed above, before processing circuit 136 provides launch signal150, processing circuit 136 charges capacitance 520 and 530. From thetime of launch, at the start of time T730, processing circuit 136controls the charging and discharge of capacitance 530 to form pulses ofsignal 620 at a first rate. Because a circuit is not established with atarget at the lower voltage and higher pulse rate, processing circuit136 does not detect discharge of capacitance 520 during the period oftime T730. After the period of time T730, processing circuit 136decreases the pulse rate of signal 720, increases the magnitude of thevoltage of signal 720 from V624 to V622, and increases the voltage ofsignal 710 from V614 to V612. Processing circuit 136 then providessignals 710 and 720 at the higher voltage and signal 720 at a secondrate, that is lower than the first rate.

Signals 710 and 720 are provided through the circuit into target tissueas a stimulus signal as discussed above. When electrodes 310 and 320establish an electrical circuit with the target, capacitance 520, andcapacitance 522, discharge through the target. In this case, thedischarge of capacitance 520 does not indicate the end of the time offlight of electrodes 310 and 320 as above, so processing circuit 136 maynot determine the time of flight of electrodes 310 and 320 to thetarget. Period of time T730 is the maximum amount of time allotted forflight and establishing a circuit with a target. When period of time 730lapses without processing circuit 136 detecting the discharge ofcapacitance 520, processing circuit cannot determine a time of flight ofelectrodes 310 and 320 or the distance from the CEW to the target.

Signals 710 and 720 are provided through the circuit into target tissueas a stimulus signals as discussed above. Signal 720 provides the highvoltage portion of the stimulus signal for ionizing air in gaps toestablish electrical coupling between the electrodes and the target.Signal 710 provides the lower voltage portion of the stimulus signalthrough target tissue to impede locomotion of the target. The stimulussignal is the combination of signal 710 and signal 720.

Not discussed above is capacitance 522 and the voltage acrosscapacitance 522. The operation of capacitance 522 is analogous to theoperation of capacitance 520 and signal 710 except that the polarity ofthe voltage across capacitance 522 is the opposite of the polarity ofthe voltage across capacitance 520 so that the voltage provided bycapacitances 520 and 522 to target tissue is double the absolute valueof the magnitude of the voltage of signal 710.

The signals shown in FIG. 8 occur when the electrodes do not establishan electrical connection with the target. Similar to signal 710 in FIG.7, processing circuit 136 charges capacitance 520 and monitors thevoltage across capacitance 520 to detect formation of a circuit througha target. In FIG. 8, processing circuit 136 forms signal 820 as pulsesat a higher pulse rate and lower voltage for the predetermined time T730without detecting a decrease in the voltage across capacitance 520,which means that the electrodes have not formed a circuit with thetarget.

After the laps of period T730, processing circuit 136 provides pulses ofsignal 820 at a lower pulse rate and a higher voltage. However, in thiscase, electrodes 310 and 320 have not formed a circuit through thetarget or a short circuit with each other, so providing signal 820 atthe higher pulse rate and higher voltage will not establish, even byionization, a circuit through the target. In this example, pulses of astimulus signal at a higher voltage will not ionize air in a gap betweenelectrode 310 or electrode 320 and target tissue, so no circuit isformed through the target.

In this case the end of the time of flight of electrodes 310 and 320cannot be determined by processing circuit 136, so processing circuit136 cannot determine the time of flight of electrodes 310 and 320 to thetarget.

Not discussed above is capacitance 522 and the voltage acrosscapacitance 522. The operation of capacitance 522 is analogous to theoperation of capacitance 520 and signal 810 except that the polarity ofthe voltage across capacitance 522 is the opposite of the polarity ofthe voltage across capacitance 520 so that the voltage provided bycapacitances 520 and 522 to target tissue is double the absolute valueof the magnitude of the voltage of signal 810.

While electrodes 310 and 320 are positioned in a deployment unit priorto launch, they are positioned close (e.g., within an inch) of eachother; however, the deployment unit housing is positioned betweenelectrode 310 and electrode 320. As electrodes 310 and 320 exit thedeployment unit at launch, they are still close to each other with a gapof air between them. If the voltage level (e.g., V624) of the higherpulse rate, lower voltage signal is high enough to ionize air in the gapbetween the electrodes 310 and 320, capacitance 520, and 522, may bedischarged long before electrodes 310 and 320 reach the target.

In the event that capacitance 520, and capacitance 522, is dischargedshortly after launch, processing circuit 136 may attribute the dischargeto the proximity of electrode 310 to electrode 320 and not to theproximity of electrodes 310 and 320 to the target or a circuit throughthe target. Processing circuit may merely recharge capacitance 520, andcapacitance 522, and continue counting pulses.

Any premature discharge of capacitance 520, and 522, likely will occuronly shortly after launch of electrodes 310 and 320 because aselectrodes 310 and 320 travel toward the target, they separate from eachother thereby reducing the likelihood that higher pulse rate, lowervoltage pulses will travel between electrodes 310 and 320.

Processing circuit 136 of CEW 200 may perform, in whole or part, method1000 as shown in FIG. 10. Method 1000 includes launch 1002, start 1004,provide 1006, measure 1008, determine 1010, record 1012, calculate 1014,provide 1016, determine 1018, and record 1020.

In launch 1002, processing circuit 136 instructs launch generator 134 toprovide launch signal 150 to propulsion system 116. Launch 1002initiates the launch of electrodes 310 and 320 toward a target.Execution moves to start 1004.

In start 1004, processing circuit 136 begins to count the number oftimes pulses are formed in (e.g., provided by) ionization signal 620,720 or 820. Execution moves to provide 1006.

In provide 1006, processing circuit 136 provides each pulse of astimulus signal by charging capacitance 530 and discharging capacitance530 at a first pulse rate. Processing circuit 136 further controlsswitched power supply 510 and switch 560 to charge and dischargecapacitance 530. In the event that capacitance 520 and 522 dischargeshortly after launch, as discussed above, processing circuit 136 mayrecharge them. Execution moves to measure 1008.

In measure 1008, processing circuit 136 measures the magnitude of thevoltage across capacitance 520 (node VMP). The magnitude of the voltageacross capacitance 520 indicates the charge of capacitance 520.Execution moves to determine 1010.

In determine 1010, processing circuit 136 determines if capacitance 520has discharged. If the voltage and/or charge on capacitance 520 is zero,close to zero, or less than the magnitude of voltage V612 or V614 whencapacitance 520 is charged, then electrodes 310 and 320 likely haveestablished a circuit with a target. Processing circuit may ignore thedischarge of capacitance 520 shortly after launch for the reasonsdiscussed above. If capacitance 520 appears to have been discharged,execution moves to record 1012. Otherwise, execution moves to determine1018.

In record 1012, processing circuit 136 records the count of the numberof pulses formed since start 1004. In record 1012, processing circuit136 stores in memory the quantity of the count of pulses. Processingcircuit 136 may further store the rate at which the pulses wereprovided. Processing circuit 136 may further store information such ascurrent date and time (e.g., a timestamp), the magnitude of the voltages(e.g., V614, V624). Execution moves to calculate 1014.

In calculate 1014, processing circuit 136 uses information stored inmemory and measured to calculate the distance between CEW 200 and target350 as discussed above. Processing circuit 136 may convert the number ofpulses counted into a distance travelled by electrodes 310 and 320.Processing circuit 136 may use the distance traveled to determine adistance (e.g., spread) between electrodes 310 and 320 at the target asdiscussed above. Processing circuit 136 may store any calculatedinformation or information used to calculate information in the memoryfor storage. Information may be stored with a timestamp. Execution movesto provide 1016.

In provide 1016, processing circuit 136 provides the stimulus signal atthe lower pulse rate (e.g., second rate) and higher voltages asdiscussed above. No step is shown beyond provide 1016; however, othersteps to perform other functions follow.

In determine 1018, processing circuit 136 determines whether apredetermined timeout has occurred. If processing circuit 136 does notdetect the discharge of capacitance 520, as discussed above, processingcircuit 136 continues to provide pulses at a higher pulse rate and alower voltage until expiration of the predetermined period of time. Ifthe predetermined period, as tracked by a timer, is not expired,execution moves to measure 1008. If the predetermined period of time hasnot lapsed, execution moves to record 1020.

In record 1020, processing circuit 136 stores in memory the fact thatthe predetermined amount of time expired without detecting the dischargeof capacitance 520. The expiration of the predetermined amount of timemay be record with other data such as date and time.

Further embodiments of the disclosure are provided below.

A conducted electrical weapon (“CEW”) for determining a distance betweenthe CEW and a human or animal target, the CEW comprising: a processingcircuit; a signal generator; and at least two wire-tethered electrodes;wherein: upon launch of the at least two wire-tethered electrodes towardthe target, the signal generator provides a first series of currentpulses at a first pulse rate; the processing circuit counts each currentpulse of the first series to determine a number of current pulses of thefirst series; upon detecting that the at least two wire-tetheredelectrodes have established a circuit through the target, the signalgenerator provides a second series of current pulses at a second pulserate, the second pulse rate is less than the first pulse rate, thesecond series for impeding locomotion of the target; and in accordancewith the number of current pulses of the first series, the processingcircuit determines the distance between the CEW and the target.

The conducted electrical weapon discussed above wherein the processingcircuit multiplies a number of feet traveled by one of the at least twowire-tethered electrodes per each pulse provided at the first pulse rateby the number of current pulses of the first series to determine thedistance between the CEW and the target.

The conducted electrical weapon discussed above wherein the processingcircuit divides a velocity of flight of one of the at least twowire-tethered electrodes by the number of current pulses provided persecond at the first pulse rate to determine the number of feet traveledby the at least two wire-tethered electrodes per each pulse provided atthe first pulse rate.

A method for determining a distance between a conducted electricalweapon (“CEW”) and a human or animal target, the method performed by theCEW, the method comprising: launching a wire-tethered electrode towardthe target, the wire-tethered electrode for providing a stimulus signalto the target to impede locomotion of the target; measuring a durationof time from the launch until establishing a circuit between thewire-tethered electrode and the target; and in accordance withmeasuring, determining a distance between the CEW and the target.

The method discussed above wherein launching comprises providing alaunch signal to ignite a pyrotechnic to launch the wire-tetheredelectrode.

The method discussed above wherein measuring comprises: startingmeasurement of the duration of time at about an occurrence of a launchsignal; and stopping measurement of the duration of time upon detectingdischarge of a muscle capacitance.

The method discussed above wherein determining a distance comprisesmultiplying the duration of time and a velocity of flight of thewire-tethered electrode.

A method for determining a distance between two electrodes positioned ator near a human or animal target, the two electrodes launched from aconducted electrical weapon (“CEW”) toward the target, the methodcomprising: counting a number of pulses of a stimulus signal betweenlaunch of the electrodes toward the target and establishing anelectrical circuit through the target via the electrodes; determining afirst distance between the CEW and the target in accordance with thenumber of pulses counted; and calculating a second distance between theelectrodes in accordance with the first distance.

The foregoing description discusses embodiments, which may be changed ormodified without departing from the scope of the present disclosure asdefined in the claims. Examples listed in parentheses may be used in thealternative or in any practical combination. As used in thespecification and claims, the words ‘comprising’, ‘comprises’,‘including’, ‘includes’, ‘having’, and ‘has’ introduce an open-endedstatement of component structures and/or functions. In the specificationand claims, the words ‘a’ and ‘an’ are used as indefinite articlesmeaning ‘one or more’. When a descriptive phrase includes a series ofnouns and/or adjectives, each successive word is intended to modify theentire combination of words preceding it. For example, a black dog houseis intended to mean a house for a black dog. While for the sake ofclarity of description, several specific embodiments have beendescribed, the scope of the invention is intended to be measured by theclaims as set forth below. In the claims, the term “provided” is used todefinitively identify an object that not a claimed element but an objectthat performs the function of a workpiece. For example, in the claim “anapparatus for aiming a provided barrel, the apparatus comprising: ahousing, the barrel positioned in the housing”, the barrel is not aclaimed element of the apparatus, but an object that cooperates with the“housing” of the “apparatus” by being positioned in the “housing”.

The location indicators “herein”, “hereunder”, “above”, “below”, orother word that refer to a location, whether specific or general, in thespecification shall be construed to refer to any location in thespecification whether the location is before or after the locationindicator.

What is claimed is:
 1. A method comprising: launching, by a conductedelectrical weapon, an electrode toward a target, wherein the electrodeis configured to provide a stimulus signal to the target to impedelocomotion of the target; measuring, by the conducted electrical weapon,a time of flight of the electrode between the conducted electricalweapon and the target; and calculating, by the conducted electricalweapon, a distance between the conducted electrical weapon and thetarget based on a known velocity of deployment and the time of flight.2. The method of claim 1, wherein launching further comprises providing,by the conducted electrical weapon, a launch signal to ignite apyrotechnic to launch the electrode.
 3. The method of claim 1, whereinmeasuring further comprises: starting, by the conducted electricalweapon, a measurement of the time of flight at about an occurrence of alaunch signal; and stopping, by the conducted electrical weapon, themeasurement of the time of flight upon the electrode coupling to thetarget.
 4. The method of claim 1, further comprising providing, by theconducted electrical weapon, the stimulus signal through the electrode.5. The method of claim 4, wherein providing the stimulus signalcomprises: providing the stimulus signal at a first pulse rate prior toestablishing a circuit between the electrode and the target; andproviding the stimulus signal at a second pulse rate after establishingthe circuit between the electrode and the target.
 6. The method of claim5, wherein the stimulus signal at the first pulse rate is provided at afirst voltage and the stimulus signal at the second pulse rate isprovided at a second voltage, and wherein the first voltage is less thanthe second voltage.
 7. The method of claim 5, wherein the first pulserate is greater than the second pulse rate.
 8. The method of claim 5,wherein measuring further comprises counting a number of pulses providedat the first pulse rate.
 9. The method of claim 1, wherein calculatingthe distance comprises multiplying the known velocity of deployment bythe time of flight.
 10. A conducted electrical weapon comprising: ahandle comprising: a processing circuit; and a signal generatorconfigured to provide a stimulus signal; and a deployment unit removablyinserted within a bay of the handle, wherein the deployment unitcomprises a plurality of electrodes configured to be deployed from thedeployment unit, and wherein the processing circuit is configured toperform operations comprising: launching a first electrode from theplurality of electrodes toward a target, providing the stimulus signalto the first electrode at a first pulse rate, and determining a distancebetween the conducted electrical weapon and the target based on thefirst pulse rate of the stimulus signal.
 11. The conducted electricalweapon of claim 10, wherein the signal generator comprises a capacitanceconfigured to be charged and discharged to provide the stimulus signalat the first pulse rate.
 12. The conducted electrical weapon of claim11, wherein the processing circuit is configured to perform furtheroperations comprising counting a number of discharges of thecapacitance, wherein determining the distance is based on the number ofdischarges and the first pulse rate of the stimulus signal.
 13. A methodcomprising: deploying, by a conducted electrical weapon, a plurality ofelectrodes towards a target; measuring, by the conducted electricalweapon, a time of flight of the plurality of electrodes between theconducted electrical weapon and the target; calculating, by theconducted electrical weapon, a deployment distance between the conductedelectrical weapon and the target based on the time of flight and avelocity of deployment of the plurality of electrodes; and calculating,by the conducted electrical weapon, a spread distance between a firstelectrode and a second electrode from the plurality of electrodes,wherein the spread distance is based on the deployment distance and anangle of deployment of at least one of the first electrode and thesecond electrode.
 14. The method of claim 13, wherein the angle ofdeployment of the at least one of the first electrode and the secondelectrode is based on an angle orientation of the at least one of thefirst electrode and the second electrode prior to deploying theplurality of electrodes.
 15. The method of claim 14, wherein the angleorientation is a fixed angle based on a deployment unit housing theplurality of electrodes.
 16. The method of claim 13, further comprisingrecording, by the conducted electrical weapon, at least one of the timeof flight, the deployment distance, the angle of deployment, and thespread distance in a memory.
 17. The method of claim 16, furthercomprising transmitting, by the conducted electrical weapon, the atleast one of the time of flight, the deployment distance, the angle ofdeployment, and the spread distance to a server.
 18. The method of claim13, further comprising providing, by the conducted electrical weapon, astimulus signal via at least one electrode from the plurality ofelectrodes, wherein the stimulus signal is provided at a first pulserate prior to establishing a circuit between at least two electrodesfrom the plurality of electrodes and the target and at a second pulserate after establishing the circuit between the at least two electrodesfrom the plurality of electrodes and the target.
 19. The method of claim18, wherein the stimulus signal during the first pulse rate has avoltage less than the stimulus signal during the second pulse rate. 20.The method of claim 13, wherein calculating the spread distancecomprises multiplying the deployment distance by a tangent of the angleof deployment.